1. Field of the Invention
The present invention relates generally to medical devices and methods and more particularly to apparatus and methods for providing embolic protection to a patient's aortic arch vessels during cardiac surgery and interventional cardiology procedures.
Cerebral embolism is a known complication of cardiac surgery, cardiopulmonary bypass and catheter-based interventional cardiology and electrophysiology procedures. Embolic particles, which may include thrombus, atheroma, and lipids, may become dislodged by surgical or catheter manipulations and enter the bloodstream, embolizing in the brain or other vital organs downstream. Cerebral embolism can lead to neuropsychological deficits, stroke and even death.
Prevention of embolism would benefit patients and improve the outcome of many surgical procedures. Many current devices for preventing cerebral embolism may be less than ideal in various respects. For example, such current devices may involve multiple components and multiple steps, making the use of such devices cumbersome and even injury-prone for the patient. Also, when used with other catheter-based interventional tools, the patient's vasculature may need to be accessed at multiple points and through multiple paths. For example, a current embolic protection device may be advanced into the aortic arch through the descending aorta while other catheter-based interventional tools may then need to be advanced into or into proximity with the heart through other blood vessels including the vena cava, the right common carotid artery, and the left common carotid artery.
U.S. Patent Publ. 2013/0178891, commonly assigned herewith, describes an embolic protection device having embolic protection elements that are combined with an access sheath suitable advancing a diagnostic catheter. The embolic protection elements include an embolic filter slidably mounted on a distal portion of the sheath, a proximal stop for limiting the proximal movement of the embolic filter, and a distal stop for limiting the distal movement of the embolic filter. The filter comprises a porous mesh material defining a collection chamber for captured emboli and has a collapsed and a deployed configuration. The filter may be collapsed by an access sheath used with the catheter. An access sheath may comprise a tubular main body and an embolic filter mounted on the distal portion of the tubular main body. The embolic filter may revert into the central lumen of the sheath or may be constrained on the exterior of the sheath with a larger diameter outer tube.
While very effective for protecting the aortic branch vessels from emboli, the illustrated access sheath allows only a single catheter at a time to pass through the filter. Moreover, the sheath dimensions can limit the size of catheter which can be introduced which is a particular concern if a valvuloplasty catheter or prosthetic aortic or other valve is to be delivered over the aortic arch to the heart. Therefore, improved devices, systems, and methods for preventing embolism during cardiac procedures performed over the aortic arch that overcome at least some of the aforementioned short-comings are desired.
2. Description of the Background Art
U.S. Patent Publ. 2013/0178891 has been described above. Other devices for capturing or blocking emboli to prevent cerebral embolism are described in the following patent application and patent publications: U.S. Pub. No. 2010/0312268 to Belson, entitled “Embolic Protection Device”; U.S. Pub. No. 2004/0215167 to Belson, entitled “Embolic Protection Device”; U.S. Pub. No. 2003/0100940 to Yodfat, entitled “Implantable Intraluminal Protector Device and Method of Using Same for Stabilizing Atheromoas”; PCT Pub. No. WO/2004/019817 to Belson, entitled “Embolic Protection Device”; U.S. Pat. No. 6,537,297 to Tsugita et al., entitled “Methods of Protecting a Patient from Embolization During Surgery”; U.S. Pat. No. 6,499,487 to McKenzie et al., entitled “Implantable Cerebral Protection Device and Method of Use”; U.S. Pat. No. 6,371,935 to Macoviak et al., entitled “Aortic Catheter with Flow Divider and Methods for Preventing Cerebral Embolization”; U.S. Pat. No. 6,361,545 to Macoviak et al., entitled “Perfusion Filter Catheter”; U.S. Pat. No. 6,254,563 to Macoviak et al., entitled “Perfusion Shunt Apparatus and Method”; U.S. Pat. No. 6,139,517 to Macoviak et al., entitled “Perfusion Shunt Apparatus and Method”; and U.S. Pat. No. 5,769,819 to Barbut et al., entitled “Cannula with Associated Filter.”